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Choose the Best Traction-Adding Differential

Selecting the best limited-slip or locking differential for your 4x4 depends on many factors, including the type of off-roading you do, how much time you spend off-road, your driving style and personal preference, and your budget. In most cases there isn't one silver-bullet traction-adding device that will work great for every vehicle, driver, and specific use. There will always be compromises. The good news is that we are here to steer you in the right direction. We'll help you determine which locker or limited slip will work best for you.

First, you have to decide if you want a limited-slip or locking differential and in what axles to put them in. If you spend most of your time on the street and only venture lightly off-road, then you may find that the stock open differentials suit your needs. To venture a little farther up the trails or to handle on-road snow and ice, you might want to consider a rear limited slip and possibly a front one too. For trails with more staggered holes and situations where wheels lift off the ground, you'll find that a rear locking differential will generally take you farther than front and rear limited slips. Those of you who don't want to ever be traction limited off-road should look into locking differentials front and rear.

Many traction-adding devices have less than ideal handling quirks on-road, and sometimes the quirks surface off-road too. In most cases a limited-slip differential will operate as seamlessly as a factory open differential. Selectable lockers are a great choice for those who need the traction advantage of a true locking differential while still maintaining streetability for commuting. These lockers can be turned on and off, providing predictable and stable open-differential performance on the street and when making sharp turns off-road. They can be operated by a variety of methods depending on the brand, including a 12-volt switch, air pressure, or a cable shifter. Die-hard off-road fanatics will often choose automatic locking differentials or a rear spool for cost savings, simplicity, and reliability, taking in stride any of the handling quirks that may arise.

Keep in mind that not all traction-adding devices are compatible with every 4x4. Many newer 4x4s with ABS and stability control systems don't play well with automatic locking differentials, so it's important to ask a lot of questions before shelling out your hard-earned cash for a traction adder. In most cases, newer 4x4s will require a limited-slip or selectable locker to keep the dash from lighting up with warning lights.

Type

Case Style

Engagement Method

Pros

Cons

Characteristics

Mechanical locking differential

Full case replacement

Selectable, internal air engagement

Benefits of open differential when unlocked. Arguably the strongest locker available.

Requires air source. Air lines are fragile. Internal air leaks will cause it not to function. Cannot be manually operated in an emergency.

Engages and disengages quickly. Great choice for front differentials and front and rear in daily driven 4x4s.

Type

Case Style

Engagement Method

Pros

Cons

Characteristics

Cone-clutch limited slip

Full case replacement

Automatic

Great for front axle applicatio. The d-Rex program allows for factory rebuild when worn.

Not a locker. Clutches will eventually wear out. Cannot be rebuilt at home.

Functions as an aggressive limited slip. Pro and Race Series versions offer an even better torque bias.

Type

Case Style

Engagement Method

Pros

Cons

Characteristics

Clutch type limited slip with clutch locking differential capability

Full case replacement

Selectable, 12-volt electric engagement

Limited slip when unlocked, locker when engaged. Limited slip feature great for on-road snow and ice. Can be rebuilt at home.